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The stability of high‐energy‐density lithium metal batteries (LMBs) heavily relies on the composition of the solid electrolyte interphase (SEI) formed on lithium metal anodes. In this study, the inorganic‐rich SEI layer was achieved by incorporating bisalts additives into carbonate‐based electrolytes. Within this SEI layer, the presence of LiF, polythionate, and Li3N was observed, generated by combining 1.0 м lithium bis(trifluoromethanesulfonyl)imide in ethylene carbonate: ethyl methyl carbonate:dimethyl carbonate in a 1 : 1 : 1 volume ratio, with the addition of 2 wt% lithium difluorophosphate and 2 wt% lithium difluoro(oxalato)borate additives (EL‐DO). Furthermore, this formulation effectively mitigated corrosion of aluminum current collectors. EL‐DO exhibited outstanding performance, including an average coulombic efficiency of 98.2 % in Li||Cu cells and a stable discharge capacity of approximately 162 mAh g−1 after 200 cycles in a Li||LiNi0.8Co0.1Mn0.1O2 (NCM811) configuration. Moreover, EL‐DO displayed the potential to enhance the performance not only of LMBs but also of lithium‐ion batteries. In the case of Gr||NCM811 cell using EL‐DO, it consistently maintained high discharge capacities, even achieving around 135 mAh g−1 after the 100th cycle, surpassing the performance of other electrolytes. This study underscores the synergistic impact of bisalts additives in elevating the performance of lithium batteries. [ABSTRACT FROM AUTHOR]

The successful implementation of supercapacitors in large‐scale applications necessitates careful consideration of safety aspects, along with factors such as energy density, power density, working voltage, and cycling performance. One effective method for ensuring safety is the utilization of nonflammable trimethyl phosphate (TMP) electrolyte in supercapacitors. However, this approach suffers from the drawback of low power density due to its low ionic conductivity. To overcome this limitation, we propose the addition of co‐solvents, namely propylene carbonate, acetonitrile, and propionitrile (PN), to enhance limited electrochemical properties of TMP‐based electrolytes. We systematically investigate the impact of incorporating TMP into various organic solvents on physical and electrochemical properties. Binary electrolytes show improved ionic conductivity, capacitance, power density, energy density, and working voltage compared to the single TMP‐based electrolyte. Notably, our result highlights that the carbon‐based supercapacitors using TMP‐PN with 70 : 30 volume ratio electrolyte provide the best compromise between ionic conductivity (13.5 mS cm−1), capacitance (24.0 F g−1), energy density (13.2 Wh kg−1), power density (2.3 kW kg−1), working voltage (3.5 V), and safety. By combining the nonflammable properties of TMP with co‐solvents, we can overcome the trade‐off between safety and electrochemical performances, presenting advancement in the development of supercapacitors for energy storage applications. [ABSTRACT FROM AUTHOR]

The formation of lithium (Li) dendrites and deterioration of the mechanical integrity of Nickel (Ni)‐rich cathodes directly hinder the commercialization of high‐voltage Li metal batteries (LMBs) with Ni‐rich cathodes. Herein, a novel electrolyte was tailored by combining non‐flammable triethyl phosphate (TEP) solvent with easily‐synthesized lithium nitrate (LiNO3) as the main salt and fluoroethylene carbonate (FEC) additive. The preferential electrochemical decomposition of LiNO3 and FEC provides robust and conductive solid/cathode electrolyte interphase (SEI/CEI) layer on the surface of the anode/cathode, which can protect both electrodes effectively during long‐term cycling. Benefiting from the synergetic effect of LiNO3 and FEC, NFE−LiNO3 exhibited outstanding performances in the cells with LiNi0.6Mn0.2Co0.2O2 (Li||NMC622) under high voltage (4.3 V), achieving an extremely high average efficiency of ∼100 % with an exceptional capacity retention of 90 % after 250 cycles. This study provides useful insights into the rational design of highly efficient, non‐flammable, and low‐cost electrolyte for long‐lasting high‐voltage LMBs. [ABSTRACT FROM AUTHOR]

Optical activity (1-3) is the result of chiral molecules interacting differently with left versus right circularly polarized light. Because of this intrinsic link to molecular structure, the determination of optical activity through circular dichroism (CD) spectroscopy has long served as a routine method for obtaining structural information about chemical and biological systems in condensed phases (4-6). A recent development is time-resolved CD spectroscopy, which can in principle map the structural changes associated with biomolecular function (7) and thus lead to mechanistic insights into fundamental biological processes. But implementing time-resolved CD measurements is experimentally challenging because CD is a notoriously weak effect (a factor of [10.sup.-4]-[10.sup.-6] smaller than absorption). In fact, this problem has so far prevented time-resolved vibrational CD experiments. Here we show that vibrational CD spectroscopy with femtosecond time resolution can be realized when using heterodyned spectral interferometry to detect (8-10) the phase and amplitude of the infrared optical activity free-induction-decay field in time (much like in a pulsed NMR experiment). We show that we can detect extremely weak signals in the presence of large achiral background contributions, by simultaneously measuring with a femtosecond laser pulse the vibrational CD and optical rotatory dispersion spectra of dissolved chiral limonene molecules. We have so far only targeted molecules in equilibrium, but it would be straightforward to extend the method for the observation of ultrafast structural changes such as those occurring during protein folding or asymmetric chemical reactions. That is, we should now be in a position to produce 'molecular motion pictures' (11) of fundamental molecular processes from a chiral perspective., CD spectroscopy is considered an incisive tool for determining the secondary structure of proteins in solution (4-6,12,13). But biomolecules participating in chemical or biological reactions often undergo ultrafast structural changes [...]